Artikler, rapporter og annet (teknologi og sikkerhet): Nye registreringer
Viser treff 221-240 av 358
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Evaluating the effects of watershed subdivision on hydrological simulation by SWAT model in an Arctic watershed
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-04)The hydrological model SWAT is a state-of-the-art tool for environmental and water resources management. Like other semi-distributed models, the whole river basin in the SWAT model is delineated into smaller sub-basins prior to conducting the simulation. Watershed delineation is an importance step since it could potentially influence the modelling results. The present study aimed to conducte an ... -
Sensitivity analysis of the SWAT model to spatial distribution of precipitation in streamflow simulation in an Arctic watershed
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-04)This study approached a physically based, semi-distributed SWAT model to test the model sensitivity to the spatial distribution of precipitation. Ten scenarios of precipitation from five scattered rain gauges in an Arctic watershed Målselv in northern Norway were used as inputs to run the SWAT model. Streamflows were simulated. The model runs at monthly time interval based on the historical data of ... -
Active learning for enhanced understanding of "ship damage stability"
(Journal article; Tidsskriftsartikkel, 2018)Active Learning has always played an important part of seamen’s education. Transfer of experience have from ancient time been practiced in an active learner-centered field where unexperienced seamen got involved in their own learning by being supervised by experienced seamen, when practicing seaman related activities. This learning practice was supreme before the introduction of “modern” maritime ... -
Glacial ice impacts: Part II: Damage assessment and ice-structure interactions in accidental limit states (ALS)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-28)Floating glacial ice features of various sizes pose a substantial threat to the structural integrity of offshore structures in ice-prone regions. Relatively small ice feathers, e.g., bergy bits and growlers, are a major concern because they are more difficult to detect by marine radars and perform concurrent ice management operations, especially in extreme sea states.<p> <p>This two-part companion ... -
Stability of Vessels in an Ice-free Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09)One consequence of the declining ice cover in the Arctic is increased areas of open seas. These new open sea areas lead to some challenging aspects related to ship stability. Longer fetch lengths, associated with build-up of larger waves followed by increased conditions for sea spray icing on vessels is one aspect. Open seas in combination with cold atmospheric temperatures is a prerequisite for ... -
A Review of Hydrological Models Applied in the Permafrost-Dominated Arctic Region
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-06)The Arctic region is the most sensitive region to climate change. Hydrological models are fundamental tools for climate change impact assessment. However, due to the extreme weather conditions, specific hydrological process, and data acquisition challenges in the Arctic, it is crucial to select suitable hydrological model(s) for this region. In this paper, a comprehensive review and comparison of ... -
Prediction of remaining useful life (RUL) of Komatsu excavator under reliability analysis in the Weibull-frailty model
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-15)It is an essential task to estimate the remaining useful life (RUL) of machinery in the mining sector aimed at ensuring the production and the customer’s satisfaction. In this study, a conceptual framework was used to determine the RUL under the reliability analysis in a frailty model. The proposed framework was implemented on a Komatsu PC-1250 excavator from the Sungun copper mine. Also, the ... -
Road Transportation Challenges in the Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020)Despite all efforts to mitigate global warming, its rate and magnitude are still rising where transportation is considered to be an important contributor. In the Arctic regions however, unstable weather conditions, strong seasonal variations, and long harsh winters result in additional challenges to transportation in different ways such as those related to environment, human health, safety, and ... -
Trends in seismic data acquisition in areas with surface ice
(Peer reviewed; Bok; Chapter, 2019)The Arctic has great significance in relation to the exploration and exploitation of its huge petroleum resources. Seismic surveys are the key part of petroleum exploration. Reflected sound waves are used to produce a 3D subsurface geological model, which helps to take a decision on drilling location for potential hydrocarbon resources. Seismic surveys are very complex operations, and growing energy ... -
The Compliance Challenges in Emissions Control Regulations to Reduce Air Pollution from Shipping
(Peer reviewed; Chapter; Bokkapittel, 2019-10-14)One of the thorny problems perplexing the maritime industry is to comply with existing and soon-to-be-enacted regulations towards emissions reduction from shipping. This problem has been discussed in this study under three viewpoints: i) the marine engine efficiency, ii) the decision-making process for selecting the technologies for reducing air emissions from shipping and iii) the challenges in the ... -
Typical hydrodynamic models for aquaculture nets: A comparative study under pure current conditions
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-17)The net is regarded as the most critical component in marine aquaculture facilities as it is the only barrier which protects the environment from fish escapes. Accurate predictions of the net cage deformation and drag force on the nets are needed, both for ensuring fish welfare and for dimensioning of the mooring system. Thus, an appropriate hydrodynamic model is essential. In practice, two types ... -
A dual linear autoencoder approach for vessel trajectory prediction using historical AIS data
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-21)Advances in artificial intelligence are driving the development of intelligent transportation systems, with the purpose of enhancing the safety and efficiency of such systems. One of the most important aspects of maritime safety is effective collision avoidance. In this study, a novel dual linear autoencoder approach is suggested to predict the future trajectory of a selected vessel. Such predictions ... -
An AIS-Based Multiple Trajectory Prediction Approach for Collision Avoidance in Future Vessels
(Peer reviewed; Bok; Chapter, 2019-11-11)This study presents a method to predict the future trajectory of a target vessel using historical AIS data. The purpose of such a prediction is to aid in collision avoidance in future vessels. The method presented in this study extracts all trajectories present in an initial cluster centered about a vessel position. Features for each trajectory are then generated using Principle Component Analysis ... -
Evaluation of the water quality at Bogdalen watershed near Kvitfjell and Raudfjell wind farm area
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019)Wind energy is one of the important renewable energies that get fast development in recent years. The development of wind turbines can have potential environmental impact on the surrounding environment. Especially when the wind turbines are built near the watersheds, water quality in the watershed may be degraded. In this study, the water quality in Bogdalen watershed that in or surrounding Kvitfjell ... -
Non-contact sensing and modelling on the voltage and electric field for powered transmission line
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020)From environmental, ecological or technical perspectives, the measurement of the potential voltage, electric field near the power transmission line is essential to ensure the exposure level does not exceed the limits of the government specified. This paper develops a potential voltage model, designs experiments to verify the developed model and to evaluate the parameters in the model. An electric ... -
Decentralized System Intelligence in Data Driven Networks for Shipping Industrial Applications: Digital Models to Blockchain Technologies
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-14)Data driven networks applicable for shipping industrial applications to create decentralized system intelligence are considered in this study. Such system intelligence can facilitate to improve the respective operational efficiency in local (i.e. vessel operations) and global (i.e. logistics operations) scales in shipping as the main advantage. The main features of these data driven networks are ... -
Possible COLREGs Failures under Digital Helmsman of Autonomous Ships
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-19)Autonomous navigation will play an important role in the future of the shipping industry. Hence, this study illustrates several concepts that should support the navigation side in relation to the collision avoidance of autonomous ships. The concept of system intelligence, i.e., cloned by human navigators, as the digital helmsman to navigate future vessels is discussed in the first part of this study. ... -
Investigation on heavy metals pollution of municipal refuse leachate from Tromsø landfill, Northern Norway
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019)To investigate the heavy metal pollution in leachate from sanitary landfill site of municipal solid waste, a survey was conducted in Tromsø, Northern Norway. Results shows that contents of heavy metals in landfill leachate follow the order Mn>Zn>Ni>Cu>Cr>As>Pb>Cd>Hg, and the order of the risk of different heavy metals is: Mn>Ni>As>Zn>Cr>Pb>Cd>Hg>Cu. The concentrations of Mn and Ni in landfill leachate ... -
A Goal Programming Approach for a Fuzzy Single-Source Capacitated Facility Location Problem
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019)In this paper, we present a new mixed-integer linear goal programming (MILGP) model for a fuzzy single-source capacitated facility location problem (F-SSCFLP), in which demands are considered as triangular fuzzy values and capacity of facilities are fuzzy constraints. At first, the basic fuzzy model for the given problem is presented. Then, utilizing goal programming (GP) approach and fuzzy principals ... -
Non-Preemptive Open Shop Scheduling Considering Machine Availability
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019)This paper considers a non-preemptive open shop scheduling problem (OSSP), in which machines are not available to process jobs on known periodic interval times resulted from periodic service repair, rest period, and so on. Asymmetric transportation time between machines is considered, which can be different from one job to another. The objective is to minimize the weighted mean completion time (WMCT). ...